A conventional network architecture generally includes several routing switching devices, and each routing switching device may be connected to several host devices, and all the routing switching devices are directly or indirectly connected to a gateway device, and are connected to an external network by means of the gateway device. In the prior art, a flow detection device may be deployed on a critical path in a network. For example, for a local area network or a corporate network, a flow detection device may be deployed on a connection path of a gateway device and an external network, so as to detect overall flows of the local area network or the corporate network. However, because deploying a flow detection device on a critical path in a network can only detect overall flows of the network, it is difficult to detect flows transmitted between switching devices in the network. Therefore, in an existing manner, a flow detection device is deployed in the network, and all switching devices are connected to the flow detection device, and the flow detection device detects flows transmitted between the switching devices in the network.
During a research on the prior art, the inventor discovers that, although flows transmitted between switching devices in a network can be detected by deploying a flow detection device in the network, when there are a large number of switching devices in the network, the number of flows that need to be detected by the flow detection device is large, and therefore the flow detection device is load-imbalanced and is easy to break down.